1. Field of the Invention
The present invention relates to the field of computer networking, and more particularly to a system and method for operating and maintaining equipment at a remote location using the Internet without placing ultimate control over the equipment in the hands of the remote user.
2. Brief Description of Related Developments
The fabrication of today's semiconductors requires complex tools for processing various stages of the wafer and inspecting the wafer at each stage or layer. During wafer processing, if the production equipment varies outside of desired control limits, the equipment can be subjected to defects that produce defective devices and a loss of yield. Because of the high cost associated with these problems, many types of defect inspection instruments are employed to screen the inspection devices and locate potential problems early in the process. These defect inspection systems enable early correction of potential problems. Defect inspection tools are themselves very sophisticated systems which measure, model and compare the results of inspections performed at each production step. These inspection systems also can develop problems, which impact their ability to monitor production and accurately detect and characterize defects.
In the last two decades, the semiconductor fabrication industry has developed systems for monitoring complex capital equipment to assure proper performance. Similar systems have been employed in the medical imaging industry where the quality of performance of the equipment has a direct impact on the ability of a radiologist, for example, to detect and diagnose pathology. As in any other type of imaging system, the overall performance is the result of many variables difficult to quantify from merely observing the end result. Manually measuring these variables (or critical performance parameters) requires a significant expenditure of time, which precludes frequent evaluation and correction or centralized (off site) calibration. The time required to perform these evaluations also impacts the overall productivity and effectiveness of the imaging system.
To solve the problem of continually manually monitoring the performance of the system while having the smallest impact possible on the productivity of the system, manufacturers have developed automated external monitors having the ability to periodically and regularly sample various relevant parameters. These equipment monitors sample various sources of information: data from sensors within the equipment, results of automated quality assurance tests, detailed diagnostic information, and reliability and utilization information gathered from equipment logs. The equipment monitors and/or associated equipment analyze this information and the status of the device is evaluated, reports developed, and any significant deviation from normal automatically reported to the service provider and the customer. Notification to the service provider automatically opens a service case and initiates a series of follow-up actions to initially investigate the report, evaluate the data, diagnose the cause, and correct the problem or contact the customer to schedule a time to effect the repair.
The character of the semiconductor industry is such that competition requires that products be designed, manufactured, and marketed in the most efficient and cost effective manner possible. To achieve this end, improvements in fabrication technology have had to keep pace with the rapid improvements in the electronics industry. As such, the performance of machines in fabrication facilities must be regularly monitored to ensure that they operate as efficiently as possible.
As used herein, the term “customer” refers to a purchaser and/or user of an inspection tool or inspection tool monitoring device. A customer employs the inspection tool or inspection tool monitoring device to evaluate the quality of a semiconductor device, and may sell, integrate, or otherwise pass along the semiconductor device. An “inspection tool” or “production equipment” refers to the device used to inspect the semiconductor device, while an “inspection tool monitoring device” or “defect inspection instrument” refers to a device used to evaluate certain parameters or the performance of an inspection tool.
The standard approach to diagnosing equipment problems involves servicing equipment only when a problem is reported by a customer. When such a problem is reported, a service engineer is typically sent to the customer site and, after arriving at the site, collects inspection tool and/or inspection tool monitoring device data in an attempt to diagnose the problem. This approach results in significant equipment downtime and requires a great deal of time, effort, and cost associated with the service engineer.
This conventional, highly subjective method of manually evaluating and calibrating equipment results in greatly varied results. For example, results and down times can vary widely from one service engineer to another, and can produce a significantly increased repair time. Moreover, the standard approach of servicing a piece of equipment only when a problem is reported by a customer results in increased downtimes and lost revenue for both the customer and the service organization.
As may be appreciated, use of an automated device to monitor performance of inspection tools and inspection tool monitoring devices may subject the tool data, settings, or other related information to capture by third parties. Data networks trafficking in this sensitive data, such as the internet, may employ commonly available encryption methods such as SSL and firewalls, but customers in the rapidly changing semiconductor fabrication industry tend to be extremely reticent to expose data to such data networks unless a scheme can be devised that offers an exceedingly high level of security.